Microsoft will release Cortana in the UK and China in "weeks, not months". Image: Microsoft

Microsoft has considered Cortana on iOS and Android, but a more immediate and obvious goal is bringing its Windows Phone personal assistant to international users. First up outside the US are customers in China and the UK.

Microsoft program manager for Cortana on Windows Phone Marcus Ash confirmed Cortana's impending arrival in the UK and China will happen in "weeks, not months". Ash revealed the rollout in a tweet on Saturday, first noticed by WinBeta.

@sM4llziE I should have added one. 0. Making #Cortanaavailable in the UK and China will happen very soon. Weeks not months.

Cortana has been available in the US where it was rolled out in beta as part of the Windows Phone 8.1 developer preview update in April, giving Microsoft's mobile users an equivalent to Google Now and Apple's Siri. Windows Phone 8.1 is set to roll out to all users on 24 June.

While Microsoft has been more open to making its software and services available on other platforms, such its release of Office for the iPad, it's still very early days for its digital assistant.

In a volley of tweets over Saturday, Ash clarified Microsoft's thinking on Cortana for other platforms, noting its first priorities were to make Cortana great for Windows Phone, roll it out to more countries and use Cortana as a drawcard for consumers to choose its OS.

"In a future state, the best experience will still be for Microsoft customers that own all Windows devices. Best work is on our devices," Ash said.

Only once it's executed its Windows Phone and Windows ambitions will it consider Cortana on other devices, he noted.

Ash explained in a comment on a story on WPCentral last week that the reason it is thinking about Cortana on other platforms it is an underdog in mobile. As such, Microsoft needs to "figure out what we need to so that a Microsoft customer who has a PC/tablet but a different phone can have a great Cortana experience".

"We are a challenger in the mobile space. This means we need to consider ideas and alternatives to breakthrough and be flexible and adaptable based on what we learn as Cortana comes to Windows Phone customers," Ash said.